diff --git a/Gruntfile.js b/Gruntfile.js
index 9a1031239803babbd8f79a1d4355314179cfd8b8..5f7b6b342e9cebb0b224036de5f819c8a90b63ab 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -331,7 +331,8 @@ module.exports = function (grunt) {
         relaxerror: [
           'Element img is missing required attribute src.',
           'Attribute autocomplete not allowed on element input at this point.',
-          'Attribute autocomplete not allowed on element button at this point.'
+          'Attribute autocomplete not allowed on element button at this point.',
+          'Bad value separator for attribute role on element li.'
         ]
       },
       files: {